<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>监听器语法</title>
    <script src="/js/vue.js"></script>
</head>

<body>
    <div id="#app">
        <p>{{msg}}</p>
    </div>
</body>
<script>
    var vm = new Vue({
        el: '#app',
        data: {
          msg:'hello',
            val:'简单对象初始值',
            obj:{
                name:"复杂对象name",
                value:"复杂对象value",
            }
        },
        watch:{
            val:function(newval,oldval){
                console.log(newval,oldval);
                console.log(this.val);
            },
            obj:{
                deep:true,
                handler:function(new_val,old_val){
                    console.log(new_val,old_val)
                }
            }
        }
        
        
    })
</script>
</body>

</html>